--- a/scripts/image/ind2rgb.m
+++ b/scripts/image/ind2rgb.m
@@ -92,6 +92,7 @@
 %! assert (ergb, rgb);
 %!test
 %! ## Check that values below lower bound are mapped to first color value
+%! warning ("off", "Octave:ind2rgb:invalid-idx-img", "local");
 %! rgb = ind2rgb ([-1 0 2], gray (64));
 %! assert (rgb(:,1:2,:), zeros (1,2,3));
 %! assert (rgb(:,3,:), 1/63 * ones (1,1,3));

--- a/scripts/linear-algebra/condest.m
+++ b/scripts/linear-algebra/condest.m
@@ -233,6 +233,7 @@
 %! assert (cA, cA_test, -2^-6);
 
 %!test
+%! warning ("off", "Octave:nearly-singular-matrix", "local");
 %! N = 12;
 %! A = hilb (N);
 %! [rcondA, v] = condest (A);

--- a/scripts/linear-algebra/logm.m
+++ b/scripts/linear-algebra/logm.m
@@ -161,7 +161,9 @@
 
 
 %!assert (norm (logm ([1 -1;0 1]) - [0 -1; 0 0]) < 1e-5)
-%!assert (norm (expm (logm ([-1 2 ; 4 -1])) - [-1 2 ; 4 -1]) < 1e-5)
+%!test
+%! warning ("off", "Octave:logm:non-principal", "local");
+%! assert (norm (expm (logm ([-1 2 ; 4 -1])) - [-1 2 ; 4 -1]) < 1e-5);
 %!assert (logm ([1 -1 -1;0 1 -1; 0 0 1]), [0 -1 -1.5; 0 0 -1; 0 0 0], 1e-5)
 %!assert (logm (10), log (10))
 %!assert (full (logm (eye (3))), logm (full (eye (3))))

--- a/scripts/polynomial/polyfit.m
+++ b/scripts/polynomial/polyfit.m
@@ -171,6 +171,7 @@
 ## variable is not normalized properly.
 ## Also check the usage of 2nd & 3rd output arguments.
 %!test
+%! warning ("off", "Octave:nearly-singular-matrix", "local");
 %! x = [ -1196.4, -1195.2, -1194, -1192.8, -1191.6, -1190.4, -1189.2, -1188, ...
 %!       -1186.8, -1185.6, -1184.4, -1183.2, -1182];
 %! y = [ 315571.7086, 315575.9618, 315579.4195, 315582.6206, 315585.4966, ...
@@ -188,6 +189,7 @@
 %! assert (p, p0, 1000*eps);
 
 %!test
+%! warning ("off", "Octave:nearly-singular-matrix", "local");
 %! x = 1000 + (-5:5);
 %! xn = (x - mean (x)) / std (x);
 %! pn = ones (1,5);

--- a/scripts/testfun/__printf_assert__.m
+++ b/scripts/testfun/__printf_assert__.m
@@ -22,7 +22,7 @@
 ## @end deftypefn
 
 function __printf_assert__ (varargin)
-  global _assert_printf;
+  global _assert_printf = "";
   _assert_printf = cat (2, _assert_printf, sprintf (varargin{:}));
 endfunction
 

--- a/scripts/testfun/__prog_output_assert__.m
+++ b/scripts/testfun/__prog_output_assert__.m
@@ -22,7 +22,7 @@
 ## @end deftypefn
 
 function ret = __prog_output_assert__ (str)
-  global _assert_printf;
+  global _assert_printf = "";
   if (isempty (_assert_printf))
     ret = isempty (str);
   elseif (_assert_printf(end) == "\n")

--- a/test/parser.tst
+++ b/test/parser.tst
@@ -293,6 +293,7 @@
 %! assert (xyz, 1);
 
 %!test
+%! warning ("off", "Octave:num-to-str", "local");
 %! a = [97 ... % comment
 %!      'b'];
 %! assert (a, 'ab');